Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-05-02 Thread Dilip kumar
On 29 April 2014 13:28, Hadi Moshayedi Wrote, This looks like a great improvement. Repeating Nicolas's question, do you have a real-world example of such joins? I can think of some scenario where, user need to self-join and find the comparison with other tuples, For example, list down all the

Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-29 Thread Hadi Moshayedi
Hello Dilip, Query: select count(*) from t1,t2 where t1.bt2.b and t1.b 12000; Test Result: Nest Loop Join with Index Scan : 1653.506 ms Sort Merge Join for (seq scan) : 610.257ms This looks like a great improvement. Repeating Nicolas's

Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-28 Thread Dilip kumar
On 10 April 2014 14:21, I wrote I shall perform some more test, for that I need to do some more hack in the code and I will post them soon.. Test Scenario: Create table t1 (a int, b int); Create table t2 (a int, b int); Random record inserted in t1 and t2, as per

Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-09 Thread Nicolas Barbier
2014-04-09 Dilip kumar dilip.ku...@huawei.com: I would like to propose a New merge join algorithm for optimizing non ‘=’ operators. (‘’, ‘=’, ‘’, ‘=’) Do you have a real-world example use case of such joins, to offset the extra planner time that will likely have to be paid (even for queries

Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-09 Thread Dilip kumar
On 09 April 2014 13:31, Nicolas Barbier Wrote Do you have a real-world example use case of such joins, to offset the extra planner time that will likely have to be paid (even for queries for which the functionality ends up not being used)? I guess there might be queries that join on “values

Re: [HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-09 Thread Tom Lane
Dilip kumar dilip.ku...@huawei.com writes: On 09 April 2014 13:31, Nicolas Barbier Wrote Do you have a real-world example use case of such joins, to offset the extra planner time that will likely have to be paid (even for queries for which the functionality ends up not being used)? I think

[HACKERS] Proposal for Merge Join for Non '=' Operators

2014-04-08 Thread Dilip kumar
I would like to propose a New merge join algorithm for optimizing non '=' operators. ('', '=', '', '=') - Currently Merge join is only supported for '=' operator. For '' or '' operator it chooses Nest Loop Join, or Nest loop with materialization. - I think when tuple from